bivalve vs slit

bivalve

noun
  • A pericarp in which the seed case opens or splits into two parts or valves. 

  • Any mollusc belonging to the taxonomic class Bivalvia, characterized by a shell consisting of two hinged sections, such as a scallop, clam, mussel or oyster. 

slit

noun
  • A narrow cut or opening; a slot. 

  • The opening of the vagina. 

  • A woman, usually a sexually loose woman; a prostitute. 

verb
  • To split into strips by lengthwise cuts. 

  • To cut a narrow opening. 

  • To cut; to sever; to divide. 

adj
  • Having a cut narrow opening 

How often have the words bivalve and slit occurred in a corpus of books? (source: Google Ngram Viewer )